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            <div><h4 class="title">
                <a name="asio.reference.read_until.overload1"></a><a class="link" href="overload1.html"
                                                                     title="read_until (1 of 24 overloads)">read_until
                (1
                of 24 overloads)</a>
            </h4></div>
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    <p>
        Read data into a dynamic buffer sequence until it contains a specified
        delimiter.
    </p>
    <pre class="programlisting"><span class="keyword">template</span><span class="special">&lt;</span>
    <span class="keyword">typename</span> <a class="link" href="../SyncReadStream.html"
                                             title="Buffer-oriented synchronous read stream requirements">SyncReadStream</a><span
                class="special">,</span>
    <span class="keyword">typename</span> <a class="link" href="../DynamicBuffer_v1.html"
                                             title="Dynamic buffer requirements (version 1)">DynamicBuffer_v1</a><span
                class="special">&gt;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span
                class="identifier">read_until</span><span class="special">(</span>
    <span class="identifier">SyncReadStream</span> <span class="special">&amp;</span> <span
                class="identifier">s</span><span class="special">,</span>
    <span class="identifier">DynamicBuffer_v1</span> <span class="special">&amp;&amp;</span> <span class="identifier">buffers</span><span
                class="special">,</span>
    <span class="keyword">char</span> <span class="identifier">delim</span><span class="special">,</span>
    <span class="keyword">typename</span> <span class="identifier">constraint</span><span
                class="special">&lt;</span> <span class="identifier">is_dynamic_buffer_v1</span><span class="special">&lt;</span> <span
                class="keyword">typename</span> <span class="identifier">decay</span><span
                class="special">&lt;</span> <span class="identifier">DynamicBuffer_v1</span> <span class="special">&gt;::</span><span
                class="identifier">type</span> <span class="special">&gt;::</span><span class="identifier">value</span> <span
                class="special">&gt;::</span><span class="identifier">type</span>  <span class="special">=</span> <span
                class="number">0</span><span class="special">,</span>
    <span class="keyword">typename</span> <span class="identifier">constraint</span><span
                class="special">&lt;</span> <span class="special">!</span><span
                class="identifier">is_dynamic_buffer_v2</span><span class="special">&lt;</span> <span class="keyword">typename</span> <span
                class="identifier">decay</span><span class="special">&lt;</span> <span class="identifier">DynamicBuffer_v1</span> <span
                class="special">&gt;::</span><span class="identifier">type</span> <span
                class="special">&gt;::</span><span class="identifier">value</span> <span
                class="special">&gt;::</span><span class="identifier">type</span>  <span class="special">=</span> <span
                class="number">0</span><span class="special">);</span>
</pre>
    <p>
        This function is used to read data into the specified dynamic buffer sequence
        until the dynamic buffer sequence's get area contains the specified delimiter.
        The call will block until one of the following conditions is true:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                The get area of the dynamic buffer sequence contains the specified
                delimiter.
            </li>
            <li class="listitem">
                An error occurred.
            </li>
        </ul>
    </div>
    <p>
        This operation is implemented in terms of zero or more calls to the stream's
        read_some function. If the dynamic buffer sequence's get area already contains
        the delimiter, the function returns immediately.
    </p>
    <h6>
        <a name="asio.reference.read_until.overload1.h0"></a>
        <span><a name="asio.reference.read_until.overload1.parameters"></a></span><a class="link"
                                                                                     href="overload1.html#asio.reference.read_until.overload1.parameters">Parameters</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">s</span></dt>
            <dd><p>
                The stream from which the data is to be read. The type must support
                the SyncReadStream concept.
            </p></dd>
            <dt><span class="term">buffers</span></dt>
            <dd><p>
                The dynamic buffer sequence into which the data will be read.
            </p></dd>
            <dt><span class="term">delim</span></dt>
            <dd><p>
                The delimiter character.
            </p></dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.read_until.overload1.h1"></a>
        <span><a name="asio.reference.read_until.overload1.return_value"></a></span><a class="link"
                                                                                       href="overload1.html#asio.reference.read_until.overload1.return_value">Return
        Value</a>
    </h6>
    <p>
        The number of bytes in the dynamic buffer sequence's get area up to and
        including the delimiter.
    </p>
    <h6>
        <a name="asio.reference.read_until.overload1.h2"></a>
        <span><a name="asio.reference.read_until.overload1.exceptions"></a></span><a class="link"
                                                                                     href="overload1.html#asio.reference.read_until.overload1.exceptions">Exceptions</a>
    </h6>
    <div class="variablelist">
        <p class="title"><b></b></p>
        <dl>
            <dt><span class="term">asio::system_error</span></dt>
            <dd><p>
                Thrown on failure.
            </p></dd>
        </dl>
    </div>
    <h6>
        <a name="asio.reference.read_until.overload1.h3"></a>
        <span><a name="asio.reference.read_until.overload1.remarks"></a></span><a class="link"
                                                                                  href="overload1.html#asio.reference.read_until.overload1.remarks">Remarks</a>
    </h6>
    <p>
        After a successful read_until operation, the dynamic buffer sequence may
        contain additional data beyond the delimiter. An application will typically
        leave that data in the dynamic buffer sequence for a subsequent read_until
        operation to examine.
    </p>
    <h6>
        <a name="asio.reference.read_until.overload1.h4"></a>
        <span><a name="asio.reference.read_until.overload1.example"></a></span><a class="link"
                                                                                  href="overload1.html#asio.reference.read_until.overload1.example">Example</a>
    </h6>
    <p>
        To read data into a <code class="computeroutput"><span class="identifier">std</span><span
            class="special">::</span><span class="identifier">string</span></code>
        until a newline is encountered:
    </p>
    <pre class="programlisting"><span class="identifier">std</span><span class="special">::</span><span
            class="identifier">string</span> <span class="identifier">data</span><span class="special">;</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">size_t</span> <span
                class="identifier">n</span> <span class="special">=</span> <span class="identifier">asio</span><span
                class="special">::</span><span class="identifier">read_until</span><span class="special">(</span><span
                class="identifier">s</span><span class="special">,</span>
    <span class="identifier">asio</span><span class="special">::</span><span
                class="identifier">dynamic_buffer</span><span class="special">(</span><span
                class="identifier">data</span><span class="special">),</span> <span class="char">'\n'</span><span
                class="special">);</span>
<span class="identifier">std</span><span class="special">::</span><span class="identifier">string</span> <span
                class="identifier">line</span> <span class="special">=</span> <span class="identifier">data</span><span
                class="special">.</span><span class="identifier">substr</span><span class="special">(</span><span
                class="number">0</span><span class="special">,</span> <span class="identifier">n</span><span
                class="special">);</span>
<span class="identifier">data</span><span class="special">.</span><span class="identifier">erase</span><span
                class="special">(</span><span class="number">0</span><span class="special">,</span> <span
                class="identifier">n</span><span class="special">);</span>
</pre>
    <p>
        After the <code class="computeroutput"><span class="identifier">read_until</span></code> operation
        completes successfully, the string <code class="computeroutput"><span class="identifier">data</span></code>
        contains the delimiter:
    </p>
    <pre class="programlisting"><span class="special">{</span> <span class="char">'a'</span><span
            class="special">,</span> <span class="char">'b'</span><span class="special">,</span> <span class="special">...,</span> <span
            class="char">'c'</span><span class="special">,</span> <span class="char">'\n'</span><span
            class="special">,</span> <span class="char">'d'</span><span class="special">,</span> <span
            class="char">'e'</span><span class="special">,</span> <span class="special">...</span> <span
            class="special">}</span>
</pre>
    <p>
        The call to <code class="computeroutput"><span class="identifier">substr</span></code> then
        extracts the data up to and including the delimiter, so that the string
        <code class="computeroutput"><span class="identifier">line</span></code> contains:
    </p>
    <pre class="programlisting"><span class="special">{</span> <span class="char">'a'</span><span
            class="special">,</span> <span class="char">'b'</span><span class="special">,</span> <span class="special">...,</span> <span
            class="char">'c'</span><span class="special">,</span> <span class="char">'\n'</span> <span
            class="special">}</span>
</pre>
    <p>
        After the call to <code class="computeroutput"><span class="identifier">erase</span></code>,
        the remaining data is left in the buffer <code class="computeroutput"><span class="identifier">b</span></code>
        as follows:
    </p>
    <pre class="programlisting"><span class="special">{</span> <span class="char">'d'</span><span
            class="special">,</span> <span class="char">'e'</span><span class="special">,</span> <span class="special">...</span> <span
            class="special">}</span>
</pre>
    <p>
        This data may be the start of a new line, to be extracted by a subsequent
        <code class="computeroutput"><span class="identifier">read_until</span></code> operation.
    </p>
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            <div class="copyright-footer">Copyright © 2003-2022 Christopher M. Kohlhoff<p>
                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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